STAT 100 Study Guide - Midterm Guide: Bar Chart, Percentile, Box Plot

• School: Simon Fraser University
• Department: Statistics
• Course: STAT 100
• Professor: Gaitri Yapa

Document Summary

Distribution of a variable tells us what values it takes and how often. Quantitative v numerical values for arithmetic operations. Pie charts whole divided into parts, not good for comparisons. Bar graph better to compare sizes (also side by side type). Standard deviation = average distance from the mean (s/sd). Find average of squared distances then variables. Line graphs quantitative measured at intervals over time (time on x axis, variable on y axis, connect by a line). Look for overall pattern, trends (upward/downward movement over time), deviations from the pattern, seasonal variations. Histogram measures quantitative variables, look for patterns, deviations and outliers. Relative frequency histogram better for comparing 2 distributions. Simple way to describe variability is median & quartiles. Arrange smallest to largest (odd # is middle) (n + 1)/2. Q1 is middle left of m, q3 is middle right of m. Find distance of each observation from mean and square each distance.